Synchronous alternating current (AC) motors typically use sinusoidal current waveforms for operation. This results in smooth torque production for machines with a sinusoidal back-EMF profile. Square or trapezoidal current waveforms for operation of AC motors have been proposed to increase the torque output of the motors while maintaining a peak current stress. However, such methods recognize the advantage of utilizing normal sinusoidal current waveforms for operation at higher speeds. Typically, the transition between trapezoidal or square current waveforms and normal sinusoidal operation occurs at a predefined motor speed. Such transitions can be problematic due to the abrupt transition from trapezoidal to sinusoidal operation and visa versa.
Accordingly, it is desirable to provide a method and apparatus for generating trapezoidal currents and integrating the trapezoidal currents into a synchronous motor control structure in a seamless fashion. In addition, it is desirable to present a synchronous motor control method which provides enhanced low speed synchronous motor control while retaining robust motor control at higher speeds. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.